Welcome to Pathology Student!

My name is Kristine Krafts, MD, and I love teaching pathology. If you’re looking for straightforward answers to your pathology questions, you’ve come to the right place!

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ABO incompatibility in pregnancy

Q. I was reviewing for boards and had a question about blood types and pregnancy. Let's say a mother was type AO and father was type BO and the baby ended up being OO blood type. Assuming the mother and baby share blood, wouldn't the baby produce antibodies against...

How to figure out which blood type to transfuse into a patient

Here is a good question from one of our readers: "Why is blood group O+ not a universal donor?" It's pretty easy to determine which blood types can donate to which other blood types, if you're working in the field or if you've just had a (good) lecture on it. But if...

Student questions about neoplasia

Neoplasia can be a tough concept at first. You hear people talk about cancer all the time - but when we use the word "neoplasia" in pathology, it has a very specific definition, and it's not the same thing as cancer. Here are some great questions I got from a student...

What’s necrotic in fibrinoid necrosis?

We've talked here before about the 6 types of necrosis. One type, fibrinoid necrosis, is sort of an outlier - it's added at the end of the list of main types of necrosis as if it doesn't quite belong in the list (Robbins calls it a "special" type of necrosis). The...

A 48 year-old female with headaches

A 48-year-old female presents with a several-month history of persistent headaches. Her husband notes that over the past few months, the patient has seemed apathetic and depressed. On physical exam, the patient’s left leg strength is 4/5, and her gait is...

What’s up with factor XII?

Here's a great coag question from a Path Student reader: Q. I am wondering why Factor VII deficiency causes significant bleeding problems but Factor XII deficiency does not. One source I found stated that this is because the extrinsic pathway is the primary pathway in...

Eisenmenger syndrome

Q. I'm having a hard time wrapping my head around which way blood flows through congenital heart defects. In an atrial septal defect, blood moves from R-L in utero, but after birth, flow changes from L-R, and then to R-L. Does it keep playing this game of L to R and...